Effect of sulfonylureas on switching to insulin therapy (twice-daily biphasic insulin aspart 30): Comparison of twice-daily biphasic insulin aspart 30 with or without glimepiride in type 2 diabetic patients poorly controlled with sub-maximal glimepiride

AimThe aim of this study was to compare the effect of continuation or discontinuation of glimepiride upon starting insulin therapy in type 2 diabetic patients poorly controlled with sub-maximal glimepiride.MethodsThis 48-week, randomized, observational, parallel-group study consisted of a 24-week screening period and a 24-week intervention period. During the screening period, we unified the sulfonylureas to glimepiride at 3 mg/day for 8 weeks, and started biphasic insulin aspart 30 (Asp30Mix) once-daily injections for 16 weeks. At the start of the intervention period, we stepped up once- to twice-daily insulin injection and randomized the 26 patients into either continuation of glimepiride group (CONT, n = 14) or discontinuation of glimepiride group (DISCON, n = 12). The Asp30Mix dose-adjustment algorithm was used in both groups. HbA1C, plasma glucose, insulin daily dose, body weight, and number of hypoglycaemic episodes were evaluated.ResultsAt the end of the study, HbA1C improved in CONT more than in DISCON (P < 0.01), and daily dose of Asp30Mix was less in CONT than DISCON (P < 0.05). Body weight and the numbers of hypoglycaemic episodes were similar between the two groups.ConclusionContinuing glimepiride (sulfonylureas) allows a better glycaemic control with less insulin daily dose compared with discontinuing glimepride.